In recent years, digital cameras are becoming popular. The digital camera takes an image using an imaging device such as CCD and CMOS sensors, and saves image data of the taken image in a memory card built into the chassis. In these digital cameras, a lot of functions such as focusing, zooming, exposure, a shutter speed, ISO (sensitivity), and switching of imaging modes are electronically controlled.
Typically, the digital camera has a plurality of functions processed by a program, and needs many operations to select and set various items included in each function. For these operations, many external operating portions, for example, buttons are disposed on the surface of the chassis. However, when the external operating portions are disposed corresponding to the number of items or settings in each function, the number of components for the operating portions is increased. This causes a large-size chassis of the camera and complicated operations. Accordingly, there is an appropriate upper limit for the number of the external operating portions.
In the digital camera in the present situation, to realize multiple functions using a small number of buttons, on an operation screen, a plurality of hierarchies is set, multiple functions are realized using a combination of a plurality of buttons, and different functions for each mode are assigned to the same button.
Patent Document 1: JP-A-2004-69783
Patent Document 2: JP-A-2002-72051
Patent Document 3: JP-A-2002-101324
In the digital camera described in Patent Document 1, for example, the function of focusing is assigned to an endless circulation operating portion in an imaging mode, and the function of a frame-by-frame control is assigned in a playback mode.
In the video camera described in Patent Document 2, one rotary ring functions as a manual focus operation ring in a manual focus mode while functioning as a manual zoom operation ring when the mode is switched to an autofocus mode.
In the digital camera described in Patent Document 3, a plurality of functions is assigned to an operation dial. The instruction of the weakened or strengthened clicking feel during a turning operation of the operation dial in an imaging mode or a playback mode is given.
In the digital cameras in Patent Document 1, Patent Document 2, and Non-Patent Document 1, a plurality of functions is assigned to one operation ring and the operability of this operation ring is the same. In the digital camera in Patent Document 3, while the operating force amount is different, again, a plurality of functions is assigned to one operation dial with a clicking feel.
Through the observation by the inventor, the target values for the function to be set in the electronic device might be discrete values (or items) or continuous values. For example, as the function of the digital camera, the discrete values include a shutter speed, an aperture, an imaging scene (for example, a night scene or a portrait), and similar value. The continuous values include zooming, focusing, and similar value.
In the case where the control of the function to be targeted is controlled by a rotatable ring (or a dial) in a circular shape, it has been found that the operability is improved by use of a ring whose rotation is locked in a specific position when the discrete values are targeted and by use of a dial that continuously rotates when the continuous values are targeted.
However, in the conventional digital camera, when a ring is prepared corresponding to the output value of the function to be targeted. It is necessary to provide a plurality of types of rings in the digital camera. Depending on the provided type of the ring, the function to be assigned is limited. As a result, this has been causing limitations on the number, the arrangement, and the use feeling of the external operating portions.